Disk cache: Remove remaining uses of RankingsNode.pointer....

net/disk_cache/storage_block-inl.h

Index: net/disk_cache/storage_block-inl.h
===================================================================
--- net/disk_cache/storage_block-inl.h	(revision 21923)
+++ net/disk_cache/storage_block-inl.h	(working copy)
@@ -72,10 +72,16 @@
   DeleteData();
   data_ = NULL;
   modified_ = false;
-  own_data_ = false;
   extended_ = false;
 }
 
+template<typename T> void  StorageBlock<T>::StopSharingData() {
+  if (!data_ || own_data_)
+    return;
+  DCHECK(!modified_);
+  data_ = NULL;
+}
+
 template<typename T> void StorageBlock<T>::set_modified() {
   DCHECK(data_);
   modified_ = true;
@@ -91,6 +97,10 @@
   return (NULL != data_);
 }
 
+template<typename T> bool StorageBlock<T>::own_data() const {
+  return own_data_;
+}
+
 template<typename T> const Addr StorageBlock<T>::address() const {
   return address_;
 }